Is filmmaker Harold Ramis about to re-invent himself again? The 60-year-old writer/director/actor has one of the most storied resumes in Hollywood comedy. He made his name in the ’70s and early ’80s working as a writer, director, and/or actor on what he now calls his “institutional comedies” — “National Lampoon’s Animal House,” “Caddyshack,” “Stripes,” “National Lampoon’s Vacation.”

And then, after co-writing and co-starring in the two “Ghostbusters” films, he re-invented himself as a sort of metaphysical jester.

“When you’re young, you can play around,” he says today. “You can take a sketch idea and, if you can stretch it into ‘Anchorman,’ great. But I feel like I’ve done that. And the Big Ideas are so tantalizing. I find that entertaining.”

And so Ramis started making funny movies that grappled with the Big Ideas. He stuffed what he calls his “madcap redemption comedies” with psychoanalysis (“Analyze This”), existentialism (“Multiplicity”) and even mythology (“Groundhog Day,” arguably his and frequent collaborator Bill Murray’s mutual masterpiece).

And now, with “The Ice Harvest,” he’s changing his tone yet again.

The film — written by the formidable duo of Robert Benton and Richard Russo (the pair collaborated on “Twilight,” and Benton won Academy Awards for his screenplays for “Kramer vs. Kramer” and “Places in the Heart”), and set for a Thanksgiving release — is a dark crime comedy about a corrupt lawyer (John Cusack) and his nasty mentor (Billy Bob Thornton) as they attempt a Christmas Eve heist in Wichita, Kan.

“The Ice Harvest’ doesn’t fit into anything I’ve done before,” says Ramis. “I use the phrase ‘retro film noir’ to describe it. It’s very faithful to its generic antecedents — I’ve never done a piece that stylish — but it’s not an homage to anything. I was flipping through a book of lurid Italian films, and there are phrases in this film that look like those sort of over-saturated, melodramatic film posters. It’s cool-lookin’.

“And Russo and Benton are so smart — the script is infused with all sorts of mature wisdom, even though the characters are on the slide morally.”

In Focus talked with Ramis for almost an hour about a little bit of everything — “The Ice Harvest,” “Caddyshack,” the eccentricities of Billy Bob Thornton, the never-to-be-filmed plot of “Ghostbusters 3,” Ramis’ days as a psych-ward orderly, musical nakedness at Hef’s mansion, and much, much more. A transcript follows.